25 years ago a good friend of mine died during a banner pick up. He was flying a Rallye 180GT when the hook hit the ground and bounced up round the all flying stabiliser.
On snatching the banner and pulling up whilst applying power, the loop of cable tightened and forced the tailplane to pitch the a/c nose down.
In no way does this imply the cause of the accident in the OP but it sparked a sad memory for me.
Sir George Cayley